Studies On The Interaction Of Molecules And Light-induced Reaction In Mono-molecule Layer

Controlling the self-assembly of molecutes on substrates is prerequisite for the realization of molecular electronic devices.Besides that, there are many basic laws about the self-assembly which is unkown until now. So the study about self-assembly of molecules on solid surface is very important not only for zhe understanding of basic physical and chemical phenomena, but also for the fabrication of functional nanostructures.This dissertation focuses on the construction nanostructures on HOPG surfaces by interactions between molecules, and light irradiation effect on molecular architectures. l.STM method has been used to investigate the adsorption of tow DOBs on highly oriented pyrolytic graphite(HOPG) surface. R146 self-assembled into tow syructures at HOPG surface: Typ I structure is close-packed structure,and TypeII is mirror chirl structure. The hydrogen bond between C-H...F makes the formation of ordered structure. A well-defined of R162 adlayer was also prepared on HOPG, and the hydrogen bond also played an important role in its structure. 2.The nanostructures of PTCDI-Cnand CuPcOCg on HOPG surface are stuied by in-situSTM. Either of PTCDI-C13 or CuPcOC8 could form well-defined structures. But from the coardsorption of PTCDI-Cn and CuPcOCg, we only observed the phase separation.The present method from self-assembly provides a facile way to fabricate ultra-small electronic components. 3.UV light irradiation effect on the structural transformation in a self-assembled monolayer of 4-(amyloxy)-cinnamic acid (AOCA) on HOPG has been investigated by using scanning tunneling microscopy(STM). A well-defined of 4-(amyloxy)-cinnamic acid adlayer was first prepared on HOPG. After UV-light irradiation onto the adlayer, the dimerization of AOCA did take place, but the dimmers form disordered strucyure. Owing to no planer structure of AOCA dimmers and weak dimmer-substrate interaction, it is not easy to form an ordered assembly.